The primary objective is to compare the incidence of opportunistic infections with GM-CSF or placebo in patients with advanced HIV infection against a background of standard antiretroviral therapy. The secondary objective is to compare the time to new or recurrent AIDS-related clinical events including opportunistic infections and malignancies; to compare survival; to compare pharmacoeconomic and quality of life parameters; to determine the occurrence of and clinical significance of HIV upregulation due to GM-CSF in a patient population receiving antiretroviral therapy.